# Synapse API — Celo Transaction History

> Synapse API — Celo Transaction History is a paid API for AI agents from synapse-api-brown.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-10).

Retrieves paginated transaction history for addresses on the Celo blockchain, with filtering by block range, category, and direction.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/celo/tx/history?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synapse-api-celo-transaction-history-64c6b863
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gDCuq8q1An8iCnWg5jkwZ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability synapse-api-celo-transaction-history-64c6b863 -d '<json body>'
```

Example prompt: Pull the last 25 transactions for Celo address 0xABC123... in descending order, including metadata, and exclude zero-value transfers.

## When to prefer this

Choose this endpoint when you need transaction history specifically on the Celo blockchain with fine-grained filtering by block range, direction, and category. Prefer it over generic multi-chain endpoints when Celo is your target network and you need paginated, structured transfer records with optional metadata enrichment.

## Known failure modes

- Invalid or malformed address returns an error response
- Block range too large may time out or return partial results
- Invalid category values may be ignored or cause errors
- Missing required address fields returns a validation error
- pageKey expiry or invalidity causes pagination to fail
- Payment not received (x402) results in 402 Payment Required

## How this service works

High-speed API suite for AI processing, web scraping, and smart data utilities across 57+ blockchain networks. Pay-per-call via x402.

## Output

A list of transactions involving the specified Celo address(es), including transfer amounts, block numbers, transaction hashes, sender/receiver addresses, and optional metadata. Results are paginated via a pageKey for continued queries.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "order": {
   "enum": [
    "asc",
    "desc"
   ],
   "type": "string"
  },
  "pageKey": {
   "type": "string"
  },
  "toBlock": {
   "type": "string"
  },
  "category": {
   "type": "array",
   "items": {
    "type": "string"
   }
  },
  "maxCount": {
   "type": "number"
  },
  "fromBlock": {
   "type": "string"
  },
  "toAddress": {
   "type": "string"
  },
  "fromAddress": {
   "type": "string"
  },
  "withMetadata": {
   "type": "boolean"
  },
  "excludeZeroValue": {
   "type": "boolean"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-celo-transaction-history-64c6b863/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from synapse-api-brown.vercel.app](https://www.zero.xyz/host/synapse-api-brown.vercel.app/llms.txt)